by Stephen Siu-ming Wong. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1996. / Includes bibliographical references (leaves 164-170). / Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Cache Memory --- p.2 / Chapter 1.2 --- System Performance --- p.3 / Chapter 1.3 --- Cache Performance --- p.3 / Chapter 1.4 --- Cache Prefetching --- p.5 / Chapter 1.5 --- Organization of Dissertation --- p.7 / Chapter 2 --- Related Work --- p.8 / Chapter 2.1 --- Memory Hierarchy --- p.8 / Chapter 2.2 --- Cache Memory Management --- p.10 / Chapter 2.2.1 --- Configuration --- p.10 / Chapter 2.2.2 --- Replacement Algorithms --- p.13 / Chapter 2.2.3 --- Write Back Policies --- p.15 / Chapter 2.2.4 --- Cache Miss Types --- p.16 / Chapter 2.2.5 --- Prefetching --- p.17 / Chapter 2.3 --- Locality --- p.18 / Chapter 2.3.1 --- Spatial vs. Temporal --- p.18 / Chapter 2.3.2 --- Instruction Cache vs. Data Cache --- p.20 / Chapter 2.4 --- Why Not a Large L1 Cache? --- p.26 / Chapter 2.4.1 --- Critical Time Path --- p.26 / Chapter 2.4.2 --- Hardware Cost --- p.27 / Chapter 2.5 --- Trend to have L2 Cache On Chip --- p.28 / Chapter 2.5.1 --- Examples --- p.29 / Chapter 2.5.2 --- Dedicated L2 Bus --- p.31 / Chapter 2.6 --- Hardware Prefetch Algorithms --- p.32 / Chapter 2.6.1 --- One Block Look-ahead --- p.33 / Chapter 2.6.2 --- Chen's RPT & similar algorithms --- p.34 / Chapter 2.7 --- Software Based Prefetch Algorithm --- p.38 / Chapter 2.7.1 --- Prefetch Instruction --- p.38 / Chapter 2.8 --- Hybrid Prefetch Algorithm --- p.40 / Chapter 2.8.1 --- Stride CAM Prefetching --- p.40 / Chapter 3 --- Simulator --- p.43 / Chapter 3.1 --- Multi-level Memory Hierarchy Simulator --- p.43 / Chapter 3.1.1 --- Multi-level Memory Support --- p.45 / Chapter 3.1.2 --- Non-blocking Cache --- p.45 / Chapter 3.1.3 --- Cycle-by-cycle Simulation --- p.47 / Chapter 3.1.4 --- Cache Prefetching Support --- p.47 / Chapter 4 --- Proposed Algorithms --- p.48 / Chapter 4.1 --- SIRPA --- p.48 / Chapter 4.1.1 --- Rationale --- p.48 / Chapter 4.1.2 --- Architecture Model --- p.50 / Chapter 4.2 --- Line Concept --- p.56 / Chapter 4.2.1 --- Rationale --- p.56 / Chapter 4.2.2 --- "Improvement Over ""Pure"" Algorithm" --- p.57 / Chapter 4.2.3 --- Architectural Model --- p.59 / Chapter 4.3 --- Combined L1-L2 Cache Management --- p.62 / Chapter 4.3.1 --- Rationale --- p.62 / Chapter 4.3.2 --- Feasibility --- p.63 / Chapter 4.4 --- Combine SIRPA with Default Prefetch --- p.66 / Chapter 4.4.1 --- Rationale --- p.67 / Chapter 4.4.2 --- Improvement Over “Pure´ح Algorithm --- p.69 / Chapter 4.4.3 --- Architectural Model --- p.70 / Chapter 5 --- Results --- p.73 / Chapter 5.1 --- Benchmarks Used --- p.73 / Chapter 5.1.1 --- SPEC92int and SPEC92fp --- p.75 / Chapter 5.2 --- Configurations Tested --- p.79 / Chapter 5.2.1 --- Prefetch Algorithms --- p.79 / Chapter 5.2.2 --- Cache Sizes --- p.80 / Chapter 5.2.3 --- Cache Block Sizes --- p.81 / Chapter 5.2.4 --- Cache Set Associativities --- p.81 / Chapter 5.2.5 --- "Bus Width, Speed and Other Parameters" --- p.81 / Chapter 5.3 --- Validity of Results --- p.83 / Chapter 5.3.1 --- Total Instructions and Cycles --- p.83 / Chapter 5.3.2 --- Total Reference to Caches --- p.84 / Chapter 5.4 --- Overall MCPI Comparison --- p.86 / Chapter 5.4.1 --- Cache Size Effect --- p.87 / Chapter 5.4.2 --- Cache Block Size Effect --- p.91 / Chapter 5.4.3 --- Set Associativity Effect --- p.101 / Chapter 5.4.4 --- Hardware Prefetch Algorithms --- p.108 / Chapter 5.4.5 --- Software Based Prefetch Algorithms --- p.119 / Chapter 5.5 --- L2 Cache & Main Memory MCPI Comparison --- p.127 / Chapter 5.5.1 --- Cache Size Effect --- p.130 / Chapter 5.5.2 --- Cache Block Size Effect --- p.130 / Chapter 5.5.3 --- Set Associativity Effect --- p.143 / Chapter 6 --- Conclusion --- p.154 / Chapter 7 --- Future Directions --- p.157 / Chapter 7.1 --- Prefetch Buffer --- p.157 / Chapter 7.2 --- Dissimilar L1-L2 Management --- p.158 / Chapter 7.3 --- Combined LRU/MRU Replacement Policy --- p.160 / Chapter 7.4 --- N Loops Look-ahead --- p.163

<p>There is a body of research on the effect of physical activity oncognition in the old adult population. Less research areconducted on adolescents. The aim for this study is to find out ifadolescents long-term memory is affected by physical activity.144 pupils were asked to rate their physical activity each week.Thereafter their long- term memory was tested through tests onepisodic- and semantic memory. The results showed that thosewho are physically active more than 4 hours had a better scoreon part of the semantic test but no effect was found in theepisodic test. This result indicates that physical activity not onlyaffects working memory, as was shown by previous research butalso has an effect in parts of the semantic long-term memory.</p>

New materials always have the possibility of revolutionizing manufacturing processes and the way we live. Bronze, steel alloys, vulcanized rubber, ceramics, and fiber optic cables are just of few of the materials man has discovered which improved his quality of life. One of the more recent additions to the field of material science are materials that exhibit what is known as the shape memory effect. Both metals and synthetic polymers can acquire this property through processing and chemistry. However while shape memory polymers hold a lot of promise, it will require more research and development to make them affordable and useful in large scale applications. / text

Working memory and long-term memory are two types of memory associated with children’s learning and academic performance. A number of memory models have suggested there is a relationship between working memory and long-term memory; however, there is a lack of empirical research measuring this relationship using standardized assessment tools. Further, there are currently no studies measuring this relationship in children. The purpose of this study was to investigate the relationship between children’s working memory (i.e., verbal working memory, visual-spatial working memory, verbal short-term memory, visual-spatial short-term memory, and the central executive) and long-term memory, using standardized assessment tools. The Automated Working Memory Assessment was used to measure working memory and the Woodcock-Johnson Tests of Cognitive Abilities – Third Edition was used to measure long-term memory. This study utilized secondary data from a larger SSHRC funded study. Participants included 41 children between grades 1 and 8. The majority of parents who volunteered to have their children participate identified them as having a disability (e.g., speech/language difficulty; learning disability). Kendall’s tau-b revealed statistically significant correlations between four areas of working memory (i.e., verbal working memory, visual-spatial working memory, visual-spatial short-term memory, and central executive) and long-term memory. Mann-Whitney tests revealed children with higher working memory abilities differed significantly from children with lower working memory abilities on measures of long-term memory. The findings from this study may have implications for both theory and practice. The relationship observed between working memory and long-term memory appears to align with widely accepted memory models (e.g., Baddeley, 2000; Dehn, 2008). The findings also suggest interventions designed to improve children’s working memory may have the potential to enhance long-term memory abilities.

No description available.

The latent variable structure of the Wide Range Assessment of Memory and Learning (WRAML) test (Sheslow & Adams, 1990) has been suggested to contain an attention factor comprised of the subtests: Finger Windows, Number/Letter, and Sentence Memory. The multidimensional nature of the attention construct has not been addressed in previous studies with the WRAML. The present investigation was designed to investigate the relationship between the WRAML subtests and a diverse battery of attention tests. Three competing latent variable models of the attention construct were developed in which the WRAML subtests were hypothesized to be affected by different components of attention. The battery, administered to 120 males between 9 and 14 years of age consisted of the WRAML subtests, Digit Span, Arithmetic, Coding, Trails A, Trails B, Category Test, Speech Sounds Perception Test, Wisconsin Card Sorting Test, and a Continuous Performance Test.Significant correlations were obtained between all the tests in the battery. Confirmatory factor analysis results suggested that a four factor model of attention (Focus-Execute, Shift, Sustain, Encode) similar to that obtained by Mirsky and others, (1991) was the best data fit. The WRAML subtests were affected by the Encode element of attention in the current analysis. / Department of Educational Psychology

[Abstract]:Background:Baddeley and Hitch’s (1974) multi-component model of working memory (WM) has provided the basis for exploration into the nature of remembering and manipulating information over a short period of time. This model arguesthat the passive short-term storage system is not involved in the more dynamic working memory tasks and has formed the basis of much research on clinical populations known to have deficits in WM. However, other models argue that short-term memory and working memory rely on common storagefacilities. The aim of this thesis was to explore whether there is justification for the continued separation of WM into fractionated components.Schizophrenia (SZ) is associated with a wide range of cognitive deficits, including working memory problems. There is also some evidence to suggest that psychotic symptoms exist on a continuum and cognitive deficits similar to those found in SZ have been reported in people endorsing “psychotic-like” symptoms without a formal diagnosis of schizophrenia. It was hypothesizedthat the pattern of errors made by the SZ group would help to delineate the nature of deficit shown on WM tasks.Methods:General MethodsIn order to explore the structure of WM and performance of groups hypothesized to be impaired on WM tasks, a range of span and non-span tasks were administered. Forty-two (42) control subjects were recruited for the study. Based on their scores on the Schizotypal Personality Questionnaire (SPQ - Raine, 1991), this group was divided into low scoring (NCL = 27 ) and high scoring (NCH = 15) groups. Thirty (30) people with a DSM-IV diagnosis of schizophrenia were also recruited.Experiment 1Experiment one investigated the performance of these groups on simple, complex and delayed span tasks. A simple four-word recall task, with and without interference was used to examine accuracy, error types and anyrelationship to symptomatology.Experiment 2Experiment two set out to investigate the contributions to span performance. All subjects were administered measures of articulation speed, lexical access ability, and a range of STM, WM and LTM tasks.Experiment 3This experiment used a cued-recall paradigm to explore proactive interference effects by manipulating phonological and semantic representations over briefperiods. The task consisted of trials where the subject studied a series of one or two blocks of four words.Results:Experiment 1The results of this experiment replicated previous findings (Tehan, Hendry & Kocinski, 2001) of similar patterns of performance across the three tasks withperformance decrements increasing with task difficulty. The SZ group showed significant deficits even on the simple four-word span task. Patterns of errors were similar across the groups once overall levels of performance were taken into account. SZ subjects made more movement (order) errors than the other two groups and movement errors were associated with disorganised symptoms. The association between disorganised symptomsand loss of items from the end of the list were suggestive of impaired maintenance of item information. The high schizotypy control group performed below that of the low schizotypy controls, but only a few of the differences were significant.Experiment 2For both groups articulation and lexical access formed two of the composites. For the control group, all memory tasks contributed to form one single factor. For the SZ group three separate memory composites were needed. Usingregression analyses previous findings (Tehan & Lalor, 2000; Tehan, Fogarty & Ryan, 2004) were replicated for the control group with both lexical access and to a lesser degree, rehearsal speed contributing to memory performance.Rehearsal speed was a more important predictor for recall of familiar materials (such as letters and digits) in the SZ group. The reverse was true for simple word span, with lexical access making a significant impact and rehearsal speed having little impact. For more complex memory tasks,neither articulation rate nor access to lexical memory contributed to the performance of the SZ group. Once again poorer performance for the SZ group was associated with disorganised symptoms.Experiment 3The findings from this experiment revealed that even on the simple one block trials, the SZ subjects had difficulty accurately recalling the target word with acategory cue, even in the absence of distractor activity. The SZ group made more omissions and significantly more intrusion errors than the control groups. Intrusion errors were associated with disorganised symptoms on thePositive and Negative Symptom Scale (PANSS). Despite their poorer overall performance, the SZ group did not have significantly more block-1 intrusions than the control groups suggesting that the interference effects for semantic and phonemic information were the same.Conclusions:This thesis presented evidence which is somewhat supportive of a common storage approach to WM. It calls into question the need to fractionate WMinto components. The multi-component model of WM is often used to investigate performance of SZ subjects, a population know to have WM deficits. Errors across a range of STM, WM and LTM tasks were examined in a SZ group and their performance was compared to two groups of controls: agroup with high scores on a measure of psychometric schizotypy and one with low scores. Implications regarding the purported source of deficits in WM are discussed.

Diss. (sammanfattning) Stockholm : Karol. inst., 2005. / Härtill 4 uppsatser.

Thesis (PhD)-Open University. BLDSC no.DXN017034.

Thesis (M.A.)--York University, 2004. Graduate Programme in Psychology. / Typescript. Includes bibliographical references (leaves 56-62). Also available on the Internet. MODE OF ACCESS via web browser by entering the following URL: http://wwwlib.umi.com/cr/yorku/fullcit?pMQ99301